Prittie was teaching a Denali preparation course in the North Cascades in Washington state. He noticed one of the clients using an odd looking ascender.

“I’d never seen the thing before,” Prittie told ExplorersWeb. “I kind of messed with it and played around with it a bit.”

Unlike most ascenders that slide up the rope easily but lock when weighted, the Ushba ascender does not lock on its own unless the climber falls.

“It’s a little disconcerting to use at first, because it doesn’t just grab on by itself. You have to cock your wrist,” Prittie said. “But once you get through that it’s fine.”

The course, which prepares climbers for the rigors of climbing Denali, took place in March in challenging winter conditions. The guides had set up 600 feet of fixed lines for the clients to practice using their ascenders.

“It was full on blizzard with a lot of rime (ice) and that kind of stuff, and everybody -- everybody -- was having problems,” Prittie recalls. “People were maybe 100 feet apart going up and down, with the teeth in the traditional ascender cam jamming and flipping, except this Ushba. It never once was bothered by the icing on the rope. That really made a believer out of me.”

The Ushba ascenders uses cams rather than teeth to grip the rope, making it less susceptible to ice build up.

“If you’ve done enough expeditions, we’ve all been in that position, where every third move you have to stop and clean the cam off and everything,” he said.

The camming action also allows the ascender to be used going up or down a rope, or in both directions in the case of a traverse. Prittie uses them on all climbs where he expects to encounter fixed ropes, including on big wall climbs.

“I started using it a number of years ago, and I would never go back to a traditional Petzl type of design again,” he said.

And unlike traditional ascenders, the Ushba will hold a fall when if a rope breaks or an anchor fails above the climber.

“Even though they’re made out of titanium, they’re not really any lighter than a traditional aluminum ascender because there’s a little more to them,” he said. “I just like using them for the additional safety.”

The ascender was made by Ushba Mountain Works, which was purchased by Salt Lake City-based Liberty Mountain Climbing in 2004. A company spokesperson told ExplorerWeb the ascender is no longer in production, but can be found be found on eBay and other online resale sites.